Eurasian Ruffe eDNA Sampling Expanded
in Northeastern Michigan
BY ANJANETTE BOWEN ALPENA FWCO
University) collect a bottom water sample on the Cheboygan River in northeastern
Michigan while Allison Snider (Central Michigan University) records locational
information. The water samples will be analyzed for the presence of Eurasian
ruffe eDNA. Credit: Anjanette Bowen
Late this spring, staff from The Nature Conservancy (Andrew Tucker), Central Michigan University (Jennifer Bergner and Allison Snider) and the Alpena Fish and Wildlife Conservation Office (FWCO) (Anjanette Bowen and Steven Gambicki) collected and filtered water samples from a number of northern Michigan locations in eastern Lake Superior, the upper St. Marys River and northwestern Lake Huron. The samples will be processed in an effort to detect the presence of Eurasian ruffe (ruffe) genetic material in the form of environmental DNA (eDNA). This effort expanded ruffe eDNA sampling that was originally conducted during the fall of 2012 on northwestern Lake Huron.
Ruffe are an invasive fish species that was first captured in the Great Lakes from western Lake Superior in the mid-1980s and have since spread across the southern shore of Lake Superior to Tahquamenon Bay, and into areas of Lakes Huron and Michigan. Ruffe are thought to compete with native species for habitat and food resources. They were first captured in northeastern Michigan at the Thunder Bay River in Alpena during 1995. Traditional sampling captured ruffe until 2003, however, ruffe have been absent from the catch in recent years. Ruffe were also reported from other tributaries to northern Lake Huron in 2008 (Trout River in Rogers City) and 2011-2012 (Cheboygan River in Cheboygan). The status of these sightings is unknown. Subsequent traditional sampling in these areas has not captured ruffe.
In 2006 ruffe were found at the eastern edge of Lake Superior at the mouth of the Tahquamenon River. This location is near the origin of the St. Marys River – the connecting pathway between Lake Superior and northern Lake Huron. Should ruffe enter the St. Marys River, they could pose a new risk of invasion into Lake Huron. Traditional sampling in the St. Marys River has not captured ruffe. The presence or absence of eDNA is another tool that can potentially be used to help determine the status of ruffe in specific areas of northern Michigan.
The goal of sampling on Lake Superior from the upper St. Marys River to the Tahquamenon River was to use eDNA to detect whether ruffe have expanded their range from the Tahquamenon area into the St. Marys River. Ruffe are known to exist in the Tahquamenon River and Tahquamenon Bay, however, have not been detected in the St. Marys River with traditional gear. The goal of sampling on northern Lake Huron was to use eDNA to detect whether ruffe continue to persist in areas where they have been reported but not captured with traditional gear.
A total of 314 2-liter water samples were collected including 101 samples from the upper St. Marys River, 73 samples from eastern Lake Superior, and 140 samples from northwestern Lake Huron. Sampling was conducted in areas described as favorable habitat for ruffe – slow flowing river and side channels, river mouths, and back water areas. Both surface and bottom water samples were collected. The water samples were filtered in Alpena FWCO’s eDNA processing trailer. Lake Superior State University’s Aquatic Research Laboratory in Sault Ste. Marie and Bay Mills Indian Community in Brimley partnered in this effort by providing water and space to park the eDNA processing trailer. The filtered samples will be analyzed by Central Michigan University to determine the presence or absence of ruffe eDNA. Results should be available during the summer of 2013.